The Singapore-based Institute of Bioengineering and Nanotechnology (IBN) has developed a novel method to simultaneously control the size and morphology of nanoparticles, which can be used in pharmaceutical synthesis and novel biomedical applications.
This research was recently featured in the leading Chemistry journal, Angewandte Chemie, and a US patent has been filed on the invention.
Research Scientist Dr. Yu Han and IBN Executive Director Prof. Jackie Y. Ying have developed a fluorocarbon-mediated-synthesis technique that produces nanometre-sized particles of between 50 and 300 nm with tuneable pore sizes in the range of 5-30nm.
“The nanoporous nanoparticles are named after our Institute, termed ‘IBN-1’ to ‘IBN-5’. They represent a new class of materials that are tailored simultaneously with nanometre-scale particle size and nanometre-sized pores. This is a beautiful example of ‘bottom-up’ nanotechnology made possible by supramolecular chemistry,” said Prof. Ying.
Previous attempts at synthesizing such nanoparticles created particles that were limited in the type of structure, degree of structural ordering and range of pore sizes. In many cases, special vapour-phase synthesis equipment is required.
IBN’s simple wet-chemical technique, on the other hand, can be used to create a variety of nanoparticles with enormous surface areas, and very well-defined pore size and structure.
One important application of these nanoporous nanoparticles lies in the production of pure chiral drugs, which make up over one-third of all pharmaceutical drugs currently sold worldwide. Chiral drugs are comprised of “left-handed” and “right-handed” molecules, both of which are mirror images of each other. Only one of these molecules provides the therapeutic effect.
In the production process, catalysts are used to selectively synthesize the preferred chiral molecule. However, these catalysts normally exist in a homogeneous liquid phase, which makes them difficult to be separated and reused.
Prof. Ying’s group at IBN has developed novel approaches to immobilize the catalysts on nanoporous materials synthesized by its wet-chemical technique. This renders the catalysts in a solid form, enabling them to be easily recovered and reused through simple filtering or centrifuging processes. This allows for the more efficient synthesis of a wide variety of pharmaceuticals.
This improvement in the drug manufacturing process can potentially lead to greater cost savings, as the production of the chiral ingredient currently accounts for 10-40% of the total cost. IBN’s invention could potentially have a significant impact on the chiral pharmaceuticals industry, a fast-growing sector which generated $143 billion sales in 2003.
Other applications of IBN’s nanoporous nanoparticles involve therapeutic treatments like targeted drug delivery and gene therapy. Nanoparticles of varying size and structure may be created to act as carriers for drugs, genes and proteins. In addition, these porous nanoparticles can be used to host quantum dots and magnetic nanoparticles for bioimaging and quantum device applications.